Solar Activity Cycle Is Weakest in a Century

Our star is now at "solar maximum," the peak phase of its 11-year activity cycle. But this solar max is weak, and the overall current cycle, known as Solar Cycle 24, conjures up comparisons to the famously feeble Solar Cycle 14 in the early 1900s, researchers said. "None of us alive have ever seen such a weak cycle. So we will learn something," Leif Svalgaard of Stanford University told reporters here today (Dec. 11) at the annual meeting of the American Geophysical Union.

The learning has already begun. For example, scientists think they know why the solar storms that have erupted during Solar Cycle 24 have caused relatively few problems here on Earth.
The sun often blasts huge clouds of superheated particles into space, in explosions known as coronal mass ejections (CMEs). Powerful CMEs that hit Earth squarely can trigger geomagnetic storms, which in turn can disrupt radio communications, GPS signals and power grids.
But such effects have rarely been seen during Solar Cycle 24, even though the total number of CMEs hasn't dropped off much, if at all. The explanation, researchers said, lies in the reduced pressure currently present in the heliosphere, the enormous bubble of charged particles and magnetic fields that the sun puffs out around itself.
This lower pressure has allowed CMEs to expand greatly as they cruise through space, said Nat Gopalswamy of NASA's Goddard Space Flight Center in Greenbelt, Md. Indeed, Solar Cycle 24 CMEs are, on average, 38 percent bigger than those measured during the last cycle — a difference with real consequences for folks here on Earth.
"When the CMEs expand more, the magnetic field inside the CMEs has lower strength," Gopalswamy said. "So when you have lower-strength magnetic fields, then they cause milder geomagnetic storms."

Scientists also think they know why relatively few super-fast solar energetic particles, or SEPS, have been measured in Earth's neighborhood during the current cycle, which began in early 2008. It has to do with a weakened interplanetary magnetic field, another characteristic of Solar Cycle 24, they say.
Large SEP events, which can pose a danger to astronauts in Earth orbit, are created by the shock waves driven by CMEs. But fewer of these particles are getting accelerated by such shocks these days, said Joe Giacalone of the University of Arizona.
"When the magnetic field is weaker, the particles are not trapped near the shock as effectively," Giacalone said. "They're going much farther upstream and downstream of the shock wave, and it takes a lot longer for them to get to very high energies."
The strength or weakness of a solar cycle appears to be driven by the intensity of the sun's polar magnetic field during the previous cycle. The polar field is thought to feed the sunspots— dark and relatively cool patches on the sun that are the source of CMEs and solar flares — that come in during the next cycle, Gopalswamy said.
The polar field was weak during Solar Cycle 23, so researchers suspected that Solar Cycle 24 would be underwhelming. Predictions about Solar Cycle 25 should start coming in two or three years, when the polar field reappears, Svalgaard said.

 

Maybe this is a signal that our Sun is dying. It is over 4 billion years old.

 

Our sun is middle aged, plenty of life in it...even in the grand scheme of the universe.

 

10 meters doesn't seem to care

 

There'll be good openings here and there. Too bad it'll be a 11 year anemic cycle.

 

If I remember correctly, and correct me if wrong, Solar cycle 24 was forecast to be close to or better than 1958. This was the prediction of NASA and Colorado in 2007 and 2008.

 

Its all Al Gores fault with his Global Warming Nonsense!

 

If the death of the Sun will finally put an end to the incessant whining about cycle 24, then so be it.

 

Conditions really do suck. A lot. Jeez, I miss Cycle 22 and 21! Not to mention 19...

73,
Chip W1YW

 

In 2007, NASA didnt see they'd be turning Cape Canaveral into a commercial launch facility either. Basically its now a museum and a bus tour and competing with 5 other launch sites for biz....

73,
Chip W1YW

 

In the grand scheme of things it's a pretty small issue, but I am concerned this will hurt our hobby. Oh, 2 meters and the like will be fine, but darn it, HF DX was a lot of fun at the peak of the last few cycles. We might lose a few people who just liked working the world with simple equipment. (Quite possible to do this: I've gotten over 270 entities with 100W and a $3 wire.) Hopefully there will be enough good days, as well as other things to do in the hobby, that we'll all be satisfied. But it really is a pleasure to experience a period of very good conditions.

 

There is absolutely NOTHING any of us can do about it,so why worry about it. Take what we got and be happy to have it.

 

SOTA operators are still out there working the world and it seems to be growing and growing
73 Mike VK6MB

 

I don't think conditions are that bad on HF.VHF & UHF have stunk it up pretty badly but it has it's moments.HF during the day is pretty good running QRO I'd say.Plenty of DX on 75,40,& 160 at night as well if both stations are running QRO. Those QRP guys & gals may not be having as much FUN but I'm helping out the power company's bottom line every chance I get.Run QRO & make your own conditions. {:>)

Clayton
W4KVW

 

The sun is only about a third the way through its life cycle so it is not going to die (and become a red giant) any time soon. The article is grossly inaccurate as scientists don't understand why cycle 24 is as weak as it is. Hathaway, the expert at NASA, has publicly criticized solar models as being unable to explain the main features we observe. NASA got the prediction for Cycle 24 all wrong, as they missed the preceding bottom by about 2 years, were way off with the max peak sunspot number for Cycle 23, and way off for the peak of Cycle 24. The current models are being revised as scientists gain more data and understanding of the physics from more and better satellites. Until such time as we can understand the inner workings of our star, ALL of the forecasts will be based on trendology. In other words, they are making an educated guess.